I do wish they had offered a 64GB model. My current usage is about 42GB and a 64GB model would have been perfect, but there is no way I could have gotten by with 32GB model, luckily I was able to use my previous 64GB iPad for usage comparison before making the purchase and was clearly over 25GB on that unit as well. I went with the 128GB model.

I picked the 32GB, as I use it mainly for note taking at work, and work mail. For movies and other entertainment, I also have a 12" rMB that is not much bigger / heavier to carry around either.

The only reason I would want to upgrade is, when I decide to use the iPad Pro for photography as well - to take a quick look at the pictures taken from the camera, light retouching etc.

You should think how you want to use the iPad Pro and take it from their, as everyone's use case is different. What I always recommend is to get the largest size you can afford / are willing to spend, as that is usually a leading factor

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